The invention relates to an apparatus for forming a regular stack of folding boxes of unequal thickness at the ends.
An apparatus of the kind described above is disclosed by German Offenlegungsschrift No. 2,437,475. Such stacking apparatus are desirable at the output of a folding and gluing machine, since certain kinds of folding boxes have edges of different thickness. For example, the end that is on the bottom may consist of a five-ply layer of cardboard, while the upper end of the folding box consists of only two layers of cardboard. When such folding boxes are stacked, a stack, after reaching a certain height, would fall over if the boxes were all to be stacked one on the other in the same orientation. German Offenlegungsschrift No. 2,437,475 sets forth an automatic stacking apparatus which forms a first stack at a lower-level stacking station, and then feeds the oncoming folding boxes over additional conveyor belts to a higher-level stacking station, and then the one stack is turned over and laid on the other by an inverting means. In this apparatus the first stack is swung upward on a circular path and inverted, and then lowered onto the second stack. In this turnover movement the stack has to be guided between guiding surfaces. If the box sizes are different, the adjustment of these guide surfaces is difficult. In the further employment of the stack in the case of the previously known apparatus, it is also disadvantageous that the boxes in the two partial stacks are not all face up or face down, because the one stack was inverted on the other.